1. Field of the Invention
The present invention relates to a stick of a string instrument bow, string instrument bow and methods of manufacturing the stick of the string instrument how, and particularly to the string instrument bow which are formed with fiber-reinforced plastic as a base material and have a wood-grain appearance close to that of a natural wood material and to methods of manufacturing a string instrument bow.
2. Description of Related Art
Conventionally, natural wood materials have been used for a stick of a string instrument bow such as a violin, a cello, or the like. As the natural wood material, Fernambuco material, which is highly dense, hard, and tolerant of moisture, and exhibits excellent bending strength, has mainly been used.
However, it has become difficult to get the Fernambuco material due to the dramatic decline of the Fernambuco trees in recent years. Accordingly, a stick of a string instrument bow using a compound material (FRP (fiber reinforced plastic)) of resin and fibers such as carbon fibers, glass fibers, or the like instead of the natural wood material, such as the Fernambuco material, has been manufactured.
As a method of manufacturing such a stick using a compound material of carbon fibers and resin, a method of molding a curved object with a hollow structure capable of being used for a stick part of a bow of a violin by winding an FRP prepreg (pre-impregnated FRP) around a core metal, placing the resulting object within a metal mold, heating the metal mold to obtain a molded product, and then pulling out the core metal can be mentioned (see Japanese Patent No. 3541756, for example).
However, the stick of the string instrument bow made of fiber reinforced plastic obtained by using the conventional technique has a problem in that the appearance thereof is greatly different from that of the stick of the string instrument bow made of a natural wood material. Since subjective factors are included in the evaluation of the performance of a string instrument bow, and preconceived ideas based on the appearance of a stick greatly affect the evaluation of the performance of the string instrument bow by players or audiences. For this reason, it has been desired to improve the evaluation of the performance of a string instrument bow having a stick using fiber reinforced plastic by using the fiber reinforced plastic as a base material and obtaining a stick with a wood-grain appearance close to a natural wood material, and thereby improve the product value.